In electronic control devices, the unhoused semiconductors are soldered—with increased power loss—together with a few passive components on a power substrate designed for a specific application. The preferred substrate material currently in use is a DBC (direct bonded copper) ceramic substrate. The power semiconductor components are soldered onto it. The source and drain connections of the power semiconductors are then contacted with the strip conductors of the power substrate using aluminum thick wire bond connections. The connections with the plastic-coated parts of the control device housing to be inserted are also created using thick aluminum wire bonds. Multiple bonds are typically required in order to conduct the current intensities required for specific applications. When this assembly technique is used, the only way to release the dissipation heat produced in the power semiconductors is via the underside of the chip.
The thick aluminum wire bonds described above have the following two disadvantages: A particularly large number of bonds is required, and they must be formed in succession. As a result, this portion of the manufacturing procedure is particularly time-consuming. A further disadvantage of these thick aluminum wire bonds is that they have limited capability of dissipating heat from the power semiconductors.